Narrative:

First officer made takeoff from atl. I attempted to contact atl departure control. After failing to make contact, I attempted common procedures of trying different radios and transmitting from both sides of the cockpit. A quick solution did not appear at hand, so I squawked 7600, leveled at the assigned altitude of 1000 ft. At this point, we discovered the first officer's microphone had vibrated from its holder during the takeoff roll or soon after takeoff. The microphone had landed between his flight kit, button down, on the floor. This created a stuck microphone situation. We concluded it happened during takeoff because communication was normal up through accepting the takeoff clearance. The 3-4 min delay in discovering the problem was due, in part, to the fact that the suspect microphone was on the first officer's side and I had directed him to concentrate on flying the aircraft while I attempted to resolve the problem. No altitude was violated. A high pilot workload common with complying with takeoff profiles (i.e., speeds, turns, altitudes, confign changes) contributed.

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Original NASA ASRS Text

Title: MLG IS NORDO ACFT AS FO MIKE VIBRATES FROM HOLDER ON TKOF AND LANDS BUTTON DOWN ON FLOOR. STUCK MIKE.

Narrative: FO MADE TKOF FROM ATL. I ATTEMPTED TO CONTACT ATL DEP CTL. AFTER FAILING TO MAKE CONTACT, I ATTEMPTED COMMON PROCS OF TRYING DIFFERENT RADIOS AND XMITTING FROM BOTH SIDES OF THE COCKPIT. A QUICK SOLUTION DID NOT APPEAR AT HAND, SO I SQUAWKED 7600, LEVELED AT THE ASSIGNED ALT OF 1000 FT. AT THIS POINT, WE DISCOVERED THE FO'S MIKE HAD VIBRATED FROM ITS HOLDER DURING THE TKOF ROLL OR SOON AFTER TKOF. THE MIKE HAD LANDED BTWN HIS FLT KIT, BUTTON DOWN, ON THE FLOOR. THIS CREATED A STUCK MIKE SIT. WE CONCLUDED IT HAPPENED DURING TKOF BECAUSE COM WAS NORMAL UP THROUGH ACCEPTING THE TKOF CLRNC. THE 3-4 MIN DELAY IN DISCOVERING THE PROB WAS DUE, IN PART, TO THE FACT THAT THE SUSPECT MIKE WAS ON THE FO'S SIDE AND I HAD DIRECTED HIM TO CONCENTRATE ON FLYING THE ACFT WHILE I ATTEMPTED TO RESOLVE THE PROB. NO ALT WAS VIOLATED. A HIGH PLT WORKLOAD COMMON WITH COMPLYING WITH TKOF PROFILES (I.E., SPDS, TURNS, ALTS, CONFIGN CHANGES) CONTRIBUTED.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.